Method for blow molding articles having a plurality of openings

ABSTRACT

A method for blow molding a hollow article having a plurality of openings thereinto includes inserting a parison into a cavity in a multi-part mold, injecting fluid into the mold-contained parison for expanding the parison outwardly, and intermittently and independently moving a sleeve slidably mounted within a passage through the wall of the mold and a mandrel positioned within the sleeve to perforate the parison wall and to move the mandrel through the perforation to form an opening defined by a neck in the expanded parison.

United States Patent [191 Peters METHOD FOR BLOW MOLDING ARTICLES HAVINGA PLURALITY OF OPENINGS [75] Inventor: Donald L. Peters, Bartlesville,Okla.

[73] Assignee: Phillips Petroleum Company,

Bartlesville, Okla.

221 Filed: July 18, 1972 21 Appl. N6; 272,962

52 us. Cl 264/94, 264/156, 264/163,

264/296, 425/290, 425/DIG. 214 [51] Int. Cl. B29c 17/07, 82% 17/14 [58]Field of Search 264/93, 94, 96, 97, 98,

264/99, 154, 155, 296, 156, 163, 89; 425/290, DIG. 214

[56] References Cited UNITED STATES PATENTS 3,050,773 8/l962 Hagen264/98 [III] 3,821,344 [45] June 28, 1974 l/l967 Battenfeld et al.264/98 3/1970 Rogers 264/154 X Primary Examiner-Jan H. Silbaugh [57]ABSTRACT A method for blow molding a hollow article having a pluralityof openings thereinto includes inserting a parison into a cavity in amulti-part mold, injecting fluid into the mold-contained parison forexpanding the parison outwardly, and intermittently and independentlymoving a sleeve slidably mounted within a passage through the wall ofthe mold and a mandrel positioned within the sleeve to perforate theparison wall and to move the mandrel through the perforation to form anopening defined by a neck in the expanded parison.

4 Claims, 5 Drawing Figures PATENTEUJUNZEIQM 3.821 344 SHEEI 1 0f 3 IF/Gr/ SHEU 3 UF 3 v llil' METHOD FOR BLOW MOLDING ARTICLES HAVING APLURALITY OF OPENINGS It is desirable to provide a method for blowmolding a hollow article having an opening defined by a neck.

This invention therefore resides in a method for blow molding a hollowarticle having an opening thereinto. The method employes an apparatushaving a multipart mold, means for inserting a parison into a cavity ofthe mold, means for injecting fluid into the mold contained parison, amovable sleeve slidably mounted through an opening through a wall of themold, a mandrel positioned in the sleeve, and means for intermittently,independently moving the sleeve and the mandrel for forming an openingin the parison defined by a neck of the parison.

Other aspects, objects, and the several advantages of this invention areapparent to one skilled in the art from a study of this disclosure, thedrawings, and the appended claims.

The drawings are diagrammatic views of the apparatus of this invention.

FIG. I shows a diagrammatic view of a mold, first opening and neckforming apparatus, and a second opening and neck forming apparatus,

FIG. 2 shows a portion of the mold, second opening and neck formingapparatus with the sleeve and mandrel at their first position,

FIG. 3 shows the apparatus of FIG. 2 with the sleeve moving toward thesecond position,

FIG. 4 shows the apparatus of FIG. 2 with the sleeve at the secondposition and the mandrel moving toward the second position, and

FIG. 5 shows the mandrel and sleeve at the second position and startingto return to their first positions.

Referring to FIG. I, split mold 2 comprising at least two separable moldparts has a cavity 4 for receiving a parison 6 from inserting apparatus8. The mold halves close about said parison 6 trapping the upper portionthereof between neck portion 13 of mold 2 and blow pin 11 forming afirst opening 7 and forming a first neck portion 10 on the parison 6while injecting fluid via blow pin ll into a chamber 12 of the parison 6for blow molding a hollow article, as known in the art.

Referring to FIG. 1 and FIGS. 2-5, the mold 2 has a wall 16 having asecond opening 18 formed therethrough with an annular shoulder 20 formedon the walls defining the second opening 18. The opening is convenientlylocated in a lateral portion of the mold in the parting line areaalthough not restricted to that location.

A sleeve 22 has a first end 24 slidably mounted within the secondopening 18 of the mold 2. The sleeve 22 is movable between a firstposition (FIG. 2.) at which the first end 24 is spaced from the shoulder20 and a second position (FIG. 4) at which the first end 24 of thesleeve 22 is contacting the shoulder 20.

The first end 24 of the sleeve 22 preferably has first and secondannular portions 26, 28 (see FIG. 2) that.

are of different elevations with said first annular portion 26 being ofa configuration for annularly contacting the shoulder 20 at the secondposition of the sleeve 22 with the second annular portion 28 beingspaced from said shoulder 20 at said second position. With thisconfiguration, a neck-lip 30 (see FIG. 5) can be formed on the secondneck 32 of the article as hereafter more fully described.

A mandrel 34 having a first end portion 36, a middle portion 38, and asecond end portion 40 is slidably mounted within the sleeve 22 at thefirst end of portion 36 adjacent the mold cavity 4. The mandrel 34 ismovable between a first position (see FIG. 2) at which the middleportion 38 is spaced along the sleeve 22 from the first end 24 thereofand a second position (see FIG. 5) at which the middle portion 38 of themandrel extends into the mold cavity 4.

First and second means 42, 44 are connected to the respective sleeve 22and mandrel 34 for intermittently moving these associated elementsbetween their first and second positions at preselected times duringblow molding of an article from a parison.

These means 42, 44 can comprisehydraulic cylinders, cams, time delayapparatus, limit switches, and other apparatus as known in the art forintermittently moving associated elements during process cycles.

It is preferred that the first end of portion 36 of the mandrel 34 be ofa configuration for piercing the parison during movement of the mandrel34 from the first to the second position. Such a configuration could bea point or a knife edge.

The diameter of the second end portion 40 of the mandrel is less thanthe diameter of the second opening 18 adjacent the mold cavity 4 forforming the second neck on the molded article about the second openingof the molded article.

It is also preferred that the sleeve 22 and a second end portion of themandrel 34 be of a cylindrical configuration for forming a generallycylindrical second neck 32, preferably on about the parting line 46 (seeFIG. 1) of the mold halves 48, 50 (see FIG. 2). This placement willprovide for more easy construction, operation, and servicing especiallyif positioned on the extruder side of the mold.

Although the second neck and opening 32, 52 of the molded article arehere shown on the side thereof, it should be understood that the moldedarticle can be of any configuration and the second neck and opening 32,52 can be positioned at any location relative to the first neck 10formed by neck forming apparatus 54 of FIG. 1 when a suitable multipartmold is used so that stripping of the part is possible. It should alsobe understood that there can be a multiplicity of necks and openingsformed on the container by the apparatus of this invention.

In the method of this invention, the hollow parison 6 is positionedwithin a cavity of the mold 2. The mold 2 is closed about the parisonand fluid is passed into the parison 6 via blow pin 11 for expanding theparison outwardly and forming a first opening defined by a fist neck 10.

Injection is continued to expand the wall portion 58 of the parison 6(see FIG. 3) into an opening 18 through a wall 16 of the mold 2.Portions of the parison in the opening 18 are forced outwardly relativeto wall portions 58 of the opening (see FIG. 4) for forming an annularneck-lip 30 on the molded article.

The wall portion of the parison on the opening 18 is perforated and themandrel 34 is passed through the perforation of the wall portion of theparison in the opening 18 for forcing portions of the parison in theopening 18 outwardly against the wall portions 58 of the opening betweenthe mandrel 34 and the wall portions of the opening 18 for sizing thesecond opening 52 in the parison and forming a second neck 32 about saidopening 52 with said neck 32 terminating at the neck-lip 30. Theneck-lip 30 can be formed during perforating of the wall portion of theparison or prior to said perforating.

While the invention has been described in conjunction with a presentlypreferred embodiment, it obviously is not limited thereto and the moldedarticle can be formed with only one neck by the sleeve and mandrelassembly of this invention.

What is claimed is:

l. A method for molding a blow molded hollow article having a pluralityof openings thereinto, comprismg:

positioning a hollow parison within a cavity of a mold; closing the moldabout the parison and passing fluid into the parison for expanding theparison outwardly and forming a first opening thereinto;

expanding a wall portion of the parison into a passage through a wall ofthe mold;

contacting portions of the parison in the passage with a sleeve;

moving the sleeve toward the parison and mechanically forcing portionsof the parison in the passage outwardly relative to wall portions of thepassage for forming an annular neck-lip on the molded article;

perforating the wall portion of the parison in the passage to form asecond opening in the parison, and thereafter passing a mandrel throughthe sleeve and through the second opening in the wall portion of theparison in the passage for forcing portions of the parison in thepassage outwardly against the wall portions of the passage between themandrel and said wall portions of the passage while maintaining thesleeve in forcible contact with the formed lip portion for sizing thesecond opening in the parison and forming a neck about said secondopening which terminates at the neck-lip.

2. A method, as set forth in claim 1, wherein the passage through thewall of the mold is formed through a parting line of a mold having firstand second mold halves.

3. A method, as set forth in claim 1, wherein the neck-lip is formedduring perforating of the wall portion of the parison.

4. A method, as set forth in claim 1, wherein the wall portion of theparison is perforated subsequent to forming of the neck-lip.

1. A method for molding a blow molded hollow article having a pluralityof openings thereinto, comprising: positioning a hollow parison within acavity of a mold; closing the mold about the parison and passing fluidinto the parison for expanding the parison outwardly and forming a firstopening thereinto; expanding a wall portion of the parison into apassage through a wall of the mold; contacting portions of the parisonin the passage with a sleeve; moving the sleeve toward the parison andmechanically forcing portions of the parison in the passage outwardlyrelative to wall portions of the passage for forming an annular neck-lipon the molded article; perforating the wall portion of the parison inthe passage to form a second opening in the parison, and thereafterpassing a mandrel through the sleeve and through the second opening inthe wall portion of the parison in the passage for forcing portions ofthe parison in the passage outwardly against the wall portions of thepassage between the mandrel and said wall portions of the passage whilemaintaining the sleeve in forcible contact with the formed lip portionfor sizing the second opening in the parison and forming a neck aboutsaid second opening which terminates at the neck-lip.
 2. A method, asset forth in claim 1, wherein the passage through the wall of the moldis formed through a parting line of a mold having first and second moldhalves.
 3. A method, as set forth in claim 1, wherein the neck-lip isformed during perforating of the wall portion of the parison.
 4. Amethod, as set forth in claim 1, wherein the wall portion of the parisonis perforated subsequent to forming of the neck-lip.